1. Field of the Invention
The invention relates to wool-wax substitutes based on homogeneous ester mixtures of products of esterification of glycerol-polyglycerol mixtures with selected mixtures of saturated aliphatic monocarboxylic acids and dicarboxylic acids, said ester mixtures having hydroxyl numbers ranging from 20 to 100, and acid and iodine numbers under 5, as well as to a process for their preparation.
2. Discussion of Prior Art
The object of the invention is the preparation of wool-wax substitutes based on homogeneous ester mixtures whose skin-application behavior is comparable to that of natural wool wax and which can be prepared from industrially available and physiologically satisfactory raw materials. The ester mixtures prepared in accordance with the invention are suitable for use especially in the cosmetic and pharmaceutical fields and also in industrial applications as lubricant auxiliaries and plasticizers for adhesives and resins.
Wool wax, also known as lanolin, is a relatively expensive natural product. Obtaining it and purifying it are costly. The composition of wool wax can vary according to its geographic origin and the feeding conditions of the sheep. A drawback is that it frequently contains pesticides.
Contamination by detergents, bleaches, and aldehydes and ketones formed during the oxidizing treatment of the wool wax reduces the quality of the natural product. In recent years wool wax has come to be suspected as the cause of allergic reactions in sensitive skin.
Natural wool wax is a substance of complex composition. It is essentially a mixture of about 95% esters of higher fatty acids such as hydroxy-fatty acids, straight-chain and branched-chain monocarboxylic acids having from 10 to 31 carbon atoms, and cholesterol, dihydroxycholesterol and isocholesterol, aliphatic higher alcohols having from 16 to 30 carbon atoms, and higher-molecular-weight diols, in addition to small amounts of free paraffinic hydrocarbons, free acids and free alcohols.
Wool wax is obtained from sheep's wool by extraction or scouring processes. The crude product is purified in stages, bleached and deodorized and then forms a pale-yellow, viscous substance having a faint odor. Purified wool wax exhibits an excellent skin-application behavior and has been valued since time immemorial as a component of pharmaceutical and cosmetic preparations.